1. Field of the Invention
This invention is in the field of protective enclosures for electrical wiring. More particularly, this invention relates to a non-conductive protective enclosure for electrical wiring and related electrical components, which enclosure is of a size and configuration generally recognized in the trade as a junction box. Junction boxes are generally manufactured and supplied to the trade in industry-standard sizes and configurations. Some conventional junction boxes are made entirely or partially of conductive metallic material, but increasingly the electrical trade, and especially some particular applications such as electrical wiring in wet environments, call for junction boxes that are formed entirely non-conductive materials. Generally, electrical wiring terminations and electrical components are installed within such junction boxes in both residential and industrial environments. Typically, such electrical components and wiring terminations must be installed into and attached to a junction box so as to provide proper spacing between components, to provide environmental protection to the wiring terminations and components, and to prevent inadvertent contact with the wiring and components, for example, by people or animals. An important consideration is that a junction box be as spacious inside as is practicable for a particular size class in order to provide adequate room for the wiring terminations, and also be very flexible in the methods allowed for routing wires and conduits to and from the junction box.
2. Related Technology
Over the years there have been many types of electrical junction boxes developed, some for specialized usage and others for more generalized purposes, often with a view to both low cost of manufacture and to economy of use. The main purposes of such junction boxes have been to provide environmental protection for wiring terminations and electrical components installed in the boxes, while also preventing inadvertent contact by humans and animals with this wiring and electrical components.
Junction boxes have been designed in many and varying shapes and sizes, but have these above-described conventional considerations and functions in common. Many junction boxes are made to industry standard or to trade standard sizes. Earlier, junction boxes were generally constructed of metal and had only pre-formed knockouts for the attachment of conduits. When the electrician or installer found it necessary to have a hole for wire or conduit access to a junction box, this installer used a tool, such as either a punch or screwdriver, to remove a pre-formed knockout.
More recently, junction boxes have been constructed of plastics, or a mix of metals and plastics, and provide a wide variety of configurations for standard and for specialized uses. Conventional junction boxes which may be relevant to this invention include those set out in the following United States patents:                U.S. Pat. No. 5,169,013, issued Dec. 8, 1992, to Albert Lammens, Jr.;        U.S. Pat. No. 5,216,203, issued Jun. 1, 1993, to Edward E. Gower;        U.S. Pat. No. 5,352,850, issued Oct. 4, 1994, to Trevor W. Norris;        U.S. Pat. No. 5,541,363, issued Jul. 30, 1996, to Gary K. Weise, et al. (a named coinventor on the present application);        U.S. Pat. No. 5,828,001, issued Oct. 27, 1998, to Jan J. Schilhiam;        U.S. Pat. No. 5,936,200, issued Aug. 10, 1999, to Mike K. Park; and        U.S. Pat. No. 5,942,726, issued Aug. 24, 1999, to Kenneth Reiker.        
A significant disadvantage of conventional junction boxes results from their comparative inflexibility of configuration, installation, size expansion capability; and particularly with respect to inflexibility for routing and attachment of electrical conduits.